Insight into the Mechanisms of the Multicomponent Ugi and Ugi–Smiles Reactions by ESI‐MS(/MS). Issue 32 (26th September 2014)

• Record Type: Journal Article
• Authors: Iacobucci, Claudio; Reale, Samantha; Gal, Jean‐François; De Angelis, Francesco
• Is Part Of: European journal of organic chemistry. Issue 32(2014)
• Page Start: 7087
• Page End: 7090
• Publication Date: 2014-09-26
• Subjects: Multicomponent reactions -- Reaction mechanisms -- Reaction intermediates -- Rearrangement -- Mass spectrometry; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201403179
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: The mechanisms of the Ugi and Ugi–Smiles reactions were investigated by using finely selected reaction conditions that allowed all of the intermediates to be "fish‐out" and characterized by ESI‐MS/MS. New insight into the Ugi and Ugi–Smiles reaction mechanisms is provided without using charge‐tagged reagents. Characterization of the isomeric species of the Mumm rearrangement in the gas phase was performed by using MS/MS. Abstract : All key intermediates in the Ugi and Ugi–Smiles reactions are intercepted and structurally characterized by ESI‐MS/MS without the assistance of charged hooks. In particular, the coexistence of the two isomeric species of the Mumm rearrangement in the gas phase is elucidated. The reaction pathway originally hypothesized by Ugi is thus confirmed.